Same here :) the adfs is very often used in corporate environments.
I just thought that this would be a nice pro cast to go for. Since not all ruby projects are commercial and use just a simple omni with facebook etc.
Anyway if ever going for it - drop me a line :)
Building a app that uses ADFS is tricky - maybe making a screencast would be a good idea.
https://craig.io/using-microsoft-adfs-with-ruby-on-rails-and-omniauth/ there is a semi beta solution for it.